Surfer’s myelopathy is generally attributed to spinal cord ischemia resulting from prolonged hyperextension, which leads to vascular compromise [3,4]. This mechanism sets it apart from traumatic spinal cord injuries that are caused by direct impact or vertebral fractures. Although initially identified in novice surfers, similar cases have been observed in other activities that involve spinal hyperextension, including yoga, gymnastics, and swimming [5,6].

The patient had been surfing in a prone position for approximately 1 hour while on vacation. Shortly after this activity, he began experiencing back pain, which was soon followed by weakness in both lower extremities. He arrived at the emergency department 11 hours after the initial onset of symptoms and following a transfer from another hospital. A neurological examination at this time showed that his cranial nerve and upper extremity functions were intact. The sensory examination indicated no deficits. However, motor strength in the lower extremities was significantly reduced, with muscle power graded as I-II across hip, knee, and ankle flexion/extension, as well as toe dorsiflexion and plantar flexion. Deep tendon reflexes in the lower extremities were absent. Additionally, he exhibited urinary retention without the urge to urinate.

Magnetic resonance imaging of the spine showed a central T2 hyperintensity extending from T9 to the conus medullaris (Fig. 1). Analysis of the cerebrospinal fluid (CSF) indicated the presence of red blood cells (60/μL) and white blood cells (WBC; 100/μL, corrected WBC 99.88/μL), with protein (55.4 mg/dL) and glucose (73 mg/dL) levels within normal ranges. The CSF opening pressure exceeded 20 cmH₂O.

Based on his history and clinical findings, the patient was diagnosed with surfer's myelopathy. High-dose intravenous methylprednisolone (30 mg/kg) was administered 12 hours after the onset of symptoms and continued for 5 days. Subsequently, oral prednisolone was tapered over 3 weeks. Additionally, mannitol was administered, and a Foley catheter was inserted to manage urinary retention. To address urinary symptoms, the patient received anticholinergics, and beta-3 adrenergic agonists were later introduced to enhance bladder function. Intensive rehabilitation, including physiotherapy, began 2 weeks after hospitalization.

After undergoing corticosteroid therapy and intensive rehabilitation, the patient showed substantial improvement in motor function. By the time of discharge, 4 weeks after hospitalization, his motor strength in the lower extremities had improved to grade 4-5. He was able to walk with assistance, though mild urinary urgency remained. He was discharged with the capability to self-void and was scheduled to continue outpatient rehabilitation.

Over the following months, the patient demonstrated significant improvement in lower extremity motor strength and gait. At 6 months, he was able to walk independently, with motor strength graded at 5 and only mild spasticity. By the 1-year follow-up, the initially prominent urinary symptoms had almost completely resolved.

Surfer’s myelopathy predominantly affects young adults between the ages of 20 and 35, with the average age of onset around 25 years [5,6]. Pediatric cases are extremely rare, which underscores the significance of our case report involving a 7-year-old boy. In South Korea, there have been only six reported cases of surfer’s myelopathy to date [3,7,8]. Internationally, there have been reports of an 8-year-old girl developing the condition while surfing and a 7-year-old girl exhibiting similar symptoms during cheerleading [5]. These instances underscore that children, though less frequently affected, are still vulnerable to developing surfer’s myelopathy, particularly during activities that involve prolonged spinal hyperextension.

Our patient is notable not only because of his young age but also due to his significant improvement following steroid therapy and rehabilitation. This case is particularly important given the relatively small surfing population in the country.

The effectiveness of steroid therapy in treating surfer’s myelopathy seems to be inconsistent. A review of 64 reported cases found that 55% of patients who received steroids experienced improvement without any reported adverse effects. However, other case series have documented that patients remained paraplegic despite undergoing high-dose steroid therapy and extensive rehabilitation. On the other hand, some reports have shown significant neurological improvement following steroid therapy combined with fluid management.

In children, the prognosis of surfer’s myelopathy appears to be closely linked to the severity of the initial injury. Research focusing on pediatric cases indicates that the American Spinal Injury Association impairment scale (AIS) grade at the time of admission serves as a predictor of prognosis. Patients with incomplete injuries (AIS grades B-D) experienced better recovery outcomes compared to those with complete injuries (AIS grade A), who demonstrated minimal or no recovery.

Early diagnosis and treatment are crucial for improving long-term neurological outcomes. Currently, there is no standardized treatment protocol for surfer’s myelopathy, but the administration of steroids is commonly recommended, despite ongoing debates about their efficacy [3]. The literature also discusses alternative treatments such as hydration, induced hypertension, early spinal angiography with intra-arterial intervention, and intravenous tissue plasminogen activator. These treatments have been considered when steroids alone were insufficient, or as alternative interventions when steroid therapy was not initiated. Specifically, these measures were often implemented in response to cases that were refractory to corticosteroid therapy, or they were attempted independently in situations where prompt steroid administration was not feasible [3].

In this case, the early administration of high-dose methylprednisolone, initiated just 12 hours after the onset of symptoms, may have significantly contributed to the favorable prognosis. Although the effectiveness of corticosteroid therapy in surfer’s myelopathy remains uncertain due to limited evidence, early intervention could help mitigate inflammatory responses and prevent secondary damage to the spinal cord.

Typically, numbness in the lower limbs develops rapidly after the onset of back pain, often occurring within hours of surfing. However, the timing can vary between cases. This case highlights the critical need for prompt recognition and immediate treatment, which can potentially improve outcomes, even in pediatric patients.

Although CSF pleocytosis can occur in surfer’s myelopathy, it is neither a common nor a defining feature. When it does occur, it can lead to an initial misdiagnosis of infectious myelitis [8]. In instances where the CSF profile is abnormal, it more closely resembles that of a spinal cord infarction than that of an infectious process.

With the increasing popularity of surfing in South Korea, it is crucial for healthcare providers, instructors, and participants to be more aware of surfer’s myelopathy [9]. Educating novice surfers about the risks of prolonged spinal hyperextension and encouraging the adoption of proper surfing techniques are preventive measures that could help decrease the occurrence of this rare yet serious condition.

This case underscores the importance of early detection and immediate treatment of surfer's myelopathy, particularly in pediatric patients. While the effectiveness of steroid therapy is still a subject of debate, its early administration in our patient significantly enhanced neurological functions. Additional research is needed to develop clear guidelines regarding the timing and effectiveness of steroid treatment in patients with surfer's myelopathy.

This study received approval from the Institutional Review Board of Asan Medical Center (AMC IRB 2024-1266). The patient's legal guardian provided parental consent for the publication of this case report and the accompanying images.